Punch apparatus for rubber articles



Feb. 3, 1942. P. A. RAIC HE 2,272,069

7 PUNCH A'PPARATUS FOR RUBBER ARTICLES Filed May 29, 1959 INVENTOR I OMa, o

bid l ATTORNEY Patented Feb. 3,1942

. 2,272,0 9 g PUNCH APP R TUS FoR-nUB EBAnTro s Paul A. Raiche,Providence, B. 'I.,, assignor 10,

Davol Rubber Com Rhode Island P y, a corporation of j ApplicaticnMay 29,1939,, st a s); 27 ,349

l3-Claiins. (c1.-i64+ 24 My present invention relates to the manufacarticle.

.Anotherobject of my invention is to provide an apparatus :for producinga plurality of spaced perforations in a rubber article.

It is a further. object of my invention to provide an apparatus forcutting a lurality of feed passages .of-uni-form size :in a rubbernipple.

With the above and other objects and advantageousieatures in View,myfiinvention consists of a novel arrangement of parts more fully dis-iclosed .in the detailed description :following, in conjunction with theaccompanying drawing, and more specifically defined in the claimsappended'thereto.

;In the drawing:

my invention to and pressure, ewir erebyla plurality of uniform Vperforations are attained. f

.Refer n th d aw ne t e v l pu ne g v ,die'may be appl ed t a y standa dvp Q P h press; theimoyable punchrhead of such ,a-press be n indicatedas ililf'in Fi a h c spondin base o e eiv t e die be d ia V n'atedrlil.The die itself -may be made of any suitableshape and ;size't oaccommodate the arti- Fig. .11is an ,elevatiompartly 'insection andpartly broken away, showing the novel punch apparatus as used forcutting feed a n ppl I Fig. 2 is an enlarged view, in section, showingthe detailed construction of the punch die;

Fig. '3is aperspective view of the novel equalizer head;

Fig. 4 is a section, partlybroken away, on the line 4-4 of Fig. 2; and IFig. 5 is an end View on the line 55 of'Fig.v 1.

The manufacture ofrubber articles having] perforations of predeterminedsize, such as for example nipples provided with feed passages, requirespunching of-the rubber article soaslto obtain a plurality of spacedperforations of uni form'size. Since the rubber varies in thickness andin resilience,and it is difficult to provide precision tools which donot have dimensional variations and which do not appreciably wear, ithas been found desirable toprovide an-apparatus which automatically:compensates for in-.' equalities of the rubber to be, punched and forslight variations-in size, of thepunching tools. It has also been founddesirable to provide a punching apparatus which has extremely long life,and in which the parts subject to wear are passages in 1 within, theinterior surface of thev hub 24, to f the punching movement bi.

, tli'epush rod23, I f I Ihe dependinghubiZ-l is externallylthreaded'"atZ-its upper end, as indicated at 2'1, and a gen- I erally cylindricalhousing 128' is provided which is internally threaded as indicated at 29for rereadily replaceable at small cost. To this end, v

I have devised an. apparatus which includes a v =multiple power punchand a fixed die for cooper;

ating with the .multiplepunch, the. parts being 80 arranged as toequalize thepunching stroke clestobe punched, and-as illustratedincludes a" hollow supportstandard l21and a replaceable" head l3, seeFig.2, thegstandard l2 being internallyr threaded atfthe upper end is!and the lower-end of the head being correspondingly threaded toseattherein, and being formed with an annular collar I6to limitse'tting' thehead in :fixed relation to its support standard [2 The punch includes atool holder l1, withia threaded portion l8 adapted to seat in a cor're-'spondingly threaded bore vl9 of the punch head l fl,qandl. az.taperedshank for seating in a correspohdingly tapered bore 2| of .the punchhead; The holder 11, see Fig 2,has-*a central cyli-n'. drical-" boreL22forslidably receiving .a push. rod" 2 3 andrhas a depending cylindricalhub 2 l 'con-g v V centric-With the rod 23fand' forming a housing" foraheavy spiralspringiziwhich exerts a pow-1 erfulj resilient pressurejon.the push1rod 23' by engagement with acoll-arlzfi formed on the lowerend ofrod 123. ,"Iheperipheryofthe collar 25 is preferably designedto'have a :snug sliding fit provide" a guide for movable attachment tothe depending hub 24, theihdusing ZB having an elongated recessed baseportion w which isprovided with a pluralityof elongated spacedguidepassagesfi l each adapted to' 'receive a punch pins-Z112 each.punchp'in -32.

havinganenlarged head :M-and a conical-punch ing end 34, thepreferredvanglejior the conical end being about 40. Asjbest shown in Fig '2, theheads 33 'ofthepunch pinsfl are of uniform hickne 59 a to pr0 deam hbearin or the flat lowerportion of an equalizeridr ba1ancin g rockerhead r3 5, which has an upper centralconicalrrecss or depression Sfiiorreceiving, the-c0n cal or pointed end :3] of push rod ,25. Aballg andsocket -.ioint-may be used, but the conical form of universal joint ispreferred;

A spreader device 36 of cylindrical form is preferably seated about thehousing 28, and has a vertical guide slot 3'! for slidably receiving theouter end 38 of a stud which is threadedly secured in a bore 31 in thehousing 28, the lower end of the spreader being formed as a flat cutoutbase 40 provided with a plurality of openings 4| in alignment with thepunch pins 32, and the upper end of the spreader being urged downwardlytowards the die head l3 by a helical spring 42.

The die head I3, see Fig. 2, is provided with a plurality of passages 43in alignment with the punch pins 32, of uniform size, and in accord withthe desired diameter of the perforation to be made in the rubberarticle. 7

As above described, the novel punch and die includes a small number ofreadily manufactured and readily assembled parts, the punch pins andbalancing head being positioned in the housing 28 and then assembled tothe depending hub 24 l in which the rod 23 and its spring 25 have beenpreviously positioned. The spreader spring is then inserted over thehousing 28 and the spreader mounted on the housing 28 by threading thestud 38 therein through the slot 31 into the threaded cavity 39. Theheavy spiral spring 25 is tensioned by threading the housing 28 on thedepending flange 24 so as to provide a regulated resilient punch stroke.The die head I3 is then mounted in its supporting standard l2 and turnedso as to bring its openings 43 in exact alignment with the punch pins32, this turning being facilitated by providing parallel flat faces I3on opposite sides of the die head l3.

The punching operation may now be explained. The punch and die being inproper assembled relation, a nipple such as indicated in dotted lines inFig, l is positioned over the support standard l2 and the die head l3,and the punch head It is actuated in the customary manner to force thepunch downwardly. The spreader 36 contacts the upper portion of thenipple first, and flattens it as shown in Fig. 2, and the three punchpins 32 then punch downwardly under the resilient action of the spring25 to force the conical ends 34 of the punch pins into contact with thesharp upper edges of the passages 43. The conical ends of the punch pins34 thus initially penetrate through the top of the nipple, or stretchthe rubber, to permit engagement of the conical surfaces of the punchpin ends with the sharp edges of the die passages to neatly and cleanlypunch the rubber. The punchedout rubber discs contract to a diameterslightly smaller than the passage diameter, and thus drop out frombelow. Any slight difierences in the length of the punch pins 3 I, or intheir downward movement due to wear, is compensated for by theequalizing head, which positively assures sufficient downward movementof each punch pin until its head 34 has contacted the sharp upper edgeof its passageway 43. The wear which normally occurs on the conical head340i the punch pins is thus fully compensated for; the die heads l3,which are extremely hard, do not appreciably wear, and are readilyreplaceable; the life of the above described punch and die arrangementhas been found to be extremely long.

While I have described a specific punch and die construction suitablefor punching spaced perforations in nipples, it is obvious that theapparatus may be redesigned for punching spaced perforations in otherrubber articles, such as for example finger cots and the like, and maybe changed to punch any type of openings or slits in rubber articles,without departing from the spirit and the scope of the present inventionas defined in the appended claims.

I claim:

1. In combination, a die having a plurality of spaced passageways, and apunch having a plurality of separate punch elements aligned with saidpassageways, said passageways having sharp edges and said punch elementshaving conical points adapted to engage said passageway edges, and meansfor equalizing the stroke and the pressure of said punch elements,

2. In combination, a die having a plurality of spaced passageways, and apunch having a plurality of separate punch elements aligned with saidpassageways, said passageways being cylindrical and having sharp edgesand said punch elements having conical points adapted to engage saidpassageway edges, and means for equalizing the stroke and the pressureof said punch elements.

3. In combination, a. die having a plurality of spaced passageways, anda punch having a plurality of separate punch elements aligned with saidpassageways, and means comprising a punch member and an equalizingdevice actuated by said punch member and simultaneously engaging each ofsaid punch elements for equalizing the stroke and the pressure of saidpunch elements.

4. In combination, a die having a plurality of spaced passageways, and apunch having a plurality of separate punch elements aligned with saidpassageways, and means comprising a spring-pressed punch member and anequalizing device actuated by said punch member and operatively engagingsaid punch elements for equalizing the stroke and the pressure of saidpunch elements.

5. A punch comprising a block, a punch rod slidably mounted therein, acompression spring actuatable by said block and engaging said punch rod,punch elements slidably mounted in said block, and an equalizer deviceengaged by said punch rod and engaging each of'said punch elements.

6. A punch comprising a block, a punch rodslidably mounted therein, acompression spring actuatab-le by said block and engaging said punchrod, punch elements slidably mounted in said block, and an equalizerdevice having a universal connection with said punch rod and engagingeach of said punch elements. I

'7. A punch comprising a block, a punch rod slidably mounted therein, acompression spring actuatable by said block and engaging said punch rod.punch elements slidably mounted in said block, and an equalizer devicehaving a ball and socket connection with said punch rod and engagingeach of said punch elements.

8. A punch comprising a block, a punch rod slidably mounted therein, acompression spring actuatable by said block and engaging said punch rod,punch elements slidably mounted in said block, said rod having a conicalend, and an equalizer device havinga conical cavity for receiving theconical end of said punch rod and engaging each of said punch elements.

9. A punch comprising a block, a punch rod slidably mounted therein, acompression spring actuatable by said block and engaging said punch rod,punch elements slidably mounted in said. block, said rod having arounded end, and an equalizer device having a rounded cavity forreceiving the rounded end of said punch rod and engaging each of saidpunch elements.

sure of said punch elements.

spaced openings, a punch arrangement comprisfling aupunch actuatingmember and having a 10. In combination, a die having a pluralityofspaced passageways, and ar punch havingxa plurality of separate punchelements aligned with said passageways, means comprising a spring-,;'

pressed punch member and an equalizing device actuated by said punchmember and operatively engaging said punch elements for equalizing thestroke and the pressure of said punch elements,

and a spring-pressed spreader movably mounted on said punch for engagingthe work prior to plurality of spacedpa'ssages' in'alignment with thedie openings, independent punch elements 5:,v

positioned in said passages, and equalizing means positioned to beengaged by said punch actuating engagement of the punch elementstherewith. 11. In combination, adie having a plurality;

of spaced parallel passageways, and a punch hav;

ing a plurality of'separate punch elements aligned with saidpassagewaysactuating mechanism'for.

memberand to simultaneously engagethe punch elements for equalizing thestroke and pressure of said pu'nchelements. I g a 13. In, combination, adie having aplurality of spaced openings, a punch arrangementcomprisinga spring-pressed'punch actuating member and having a pluralityof spaced passages in alignment ;with the die openings; independentpunchsaid punch, and rocker means engaged by said actuating mechanism andengaging said punch" and the pres-v elements for equalizingthe stroke'12. In combination; a die having a plurality of elements positionedinsaid passages,iand equalizing means positioned to be engaged bysaid'punch f actuating member and. to simultaneously engage the punchelements for equalizing the stroke and pressure: thereof.

PAULA. RAICHE.

